@Sonos: Please refer to diagnostic 1741523771.
I cannot add my Sub to the Beam. It has been added before, but now I needed to reconnect it.
The sub shows up in the iOS app, and when asked if I want to connect the sub to an existing sepaaker I choose my Beam. Then it does it's thing, and terminates with an error telling “something went wrong”. I then did a factory reset on the Sub - same result, twice. The assigned room shows the Beam, and the ability to “remove Sub “.
I can also see in my router, and the “About my Sonos” that the Sub has been assigned an IP, and those match both in the router and in the Sonos APP.
Still no sound from my Sub, though ;-)